I need help...?

ok i have been seein this guy for over a month now.. and every thing about him bugs me, what he says, what he does... i don tknow how much longer i can take it.. ih ate bein around people who goof off and say loud or rude things in public and he does... and also my ex who i have been datin on and off again for 5 years whats me back.. but im not sure if i can trust him any more cuz he cheated on me many many times.. he will brake up with me when he thinks he has found something better then once he realizes he didnt he comes cryin to me aboutit and wants me back. yes i love my ex withall i have in me but i dont know if it will work.. HELP i need advice..